Drill heads for exploration drilling rigs are previously known that are equipped with hydraulically actuated chucks for gripping, holding and rotating pipes constituting the drill string components. The drill head is movable along a feed beam of the drilling rig while performing the rotating action during drilling.
In order to adapt the drilling mode to different drilling conditions it is previously known to provide drill heads with speed shift arrangements. One example of such a background art speed shift drill head is described in WO2013/106207.